Experimental study and thermal analysis of a tubular pressurized air receiver

Pressurized air receivers potentially used in concentrated solar power plants are being developed and studied to achieve higher systemic efficiency from solar to electricity. In this article, a novel receiver with double spiral tubes coiled into conical type was proposed and fabricated. The design shows a bending limitation of a diameter of 60 mm in the bottom of the receiver. Some experimental tests were conducted under a solar furnace in the real weather condition. The results reveal that this kind of receiver could obtain high-temperature outlet air at 908 °C with relatively low direct normal irradiation (DNI) of around 785 W/m2. Based on the comparisons of the outcomes of 9 test cases, it could be concluded that the outlet air temperature is mainly dominated by the value of DNI, while the pressure drop is determined by both DNI and mass flow rate of the air. Besides, the thermal inertia of the receiver demonstrates benefits for stable output and quick recovery induced by small adjustments in the real operation process. All of these results and analysis provide a helpful reference for validation, optimization and operational strategies for this kind of pressurized air receiver.